Returns "00000000-0000-0000-0000-000000000000" even though "Allow apps to request to track" is on.

Hello. I am currently developing an app. It returns IDFA "00000000-0000-0000-0000-000000000000" even if "Allow apps to request to track" is turned on in the device settings. Is there any way to fix this?

Thank you in advance.
Returns "00000000-0000-0000-0000-000000000000" even though "Allow apps to request to track" is on.
 
 
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